家榆种子老化过程中的细胞程序性死亡研究

Programmed cell death of Ulmus pumila L. seeds during aging

该文以家榆种子为材料,在37℃、100%相对湿度(RH)条件下老化,检测种子老化过程中细胞程序性死亡(PCD)的部分典型特征.DAPI荧光染色结果清楚地表明了老化过程中产生了凋亡小体,种子DNA电泳图谱呈现典型的“梯”状条带.细胞电解质渗漏率结果表明,细胞膜在老化过程中的一段时间内,保持了相对完整性.老化初期O2.-产生速率加快,H2O2含量激增、且O2.-产生速率、H2O2含量都维持在μmol数量级.这些特征充分证明种子老化死亡过程属于PCD范畴.

In this study, the characteristics of programmed cell death （PCD） of Ulmus pumila L. seeds were investigated. The seeds were treated at a high temperature of 37℃ and high humidity （100% relative humidity） for six days. DAPI staining revealed that the aging treatment induced condensation and margination of chromatin, as well as the formation of apoptotic bodies. The result of DNA electrophoresis of U. pumila seeds on an agarose gel showed a characteristic of ＂ladder＂ pattern. Levels of electrolyte leakage of seed cells showed that membranes remained integrally form during almost the entire aging time. There was an immediate increase of superoxide anion （O2^-.） production rate and hydrogen peroxide （H2O2） content, which stayed at μmol level. All of the above common characteristics indicate that seed aging can be classified as PCD.